Detective Cruz found an encrypted message scrawled on a foggy mirror: '5-9-12-12-15'. Applying a standard letter-to-number cipher (A=1, B=2...), it spells 'HELLO'. Cruz wiped the mirror clean with a dry cloth, and a new phrase appeared underneath. What kind of surface was it written on?
A steam-covered mirror in a bathroom.
The fog or condensation on the mirror allowed the first message to be written with a finger, and wiping it revealed the underlying glass or a pre-carved etching.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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